﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ProjectEulerSolutions
{
    /*
     * The sum of the squares of the first ten natural numbers is,
        1^2 + 2^2 + ... + 10^2 = 385

        The square of the sum of the first ten natural numbers is,
        (1 + 2 + ... + 10)^2 = 55^2 = 3025

        Hence the difference between the sum of the squares of the first ten natural numbers and the square of the sum is 3025 − 385 = 2640.

        Find the difference between the sum of the squares of the first one hundred natural numbers and the square of the sum.

     * */
    class Problem6
    {
        public static string Calculate()
        {
            int limit = 100;

            int sumofsquares = 0;
            for (int i = 1; i <= limit; i++)
            {
                sumofsquares += (int)Math.Pow(i, 2);
            }

            int squareofsums = (int) Math.Pow((limit*(limit+1)) / 2, 2);

            return (squareofsums - sumofsquares).ToString();
        }
    }
}
